Dobermans are among the most loyal, loving and defensive dogs on the planet, but you are correct.
They require direction.
Yepper, had to retire my first dobby to a junk yard, he wasn’t willing to accept my bride. No ammount of smackdown would work. She wasn’t allowed into close proximity.
The dobby is not a dog for rookie do gooders!
Donning flame proof tinfoil suit.
The same is true of pit bulls.
And germam sheperds and yady yada.
There are no bad dogs, just bad owners.
Those are the dogs that I was raised with.
They are a lot of work.
I have a black lab now LOL
Some dogs require a workout and a regime.
In short, discipline and attention.
“Smackdown”?
You reinforced his innate, albeit inappropriate wariness of your bride with “smackdowns”?
Gee.
I can’t imagine why that didn’t work.